(a) A person, entity, public agency, county, municipality, or other political subdivision of this state or another state may enter into a contract or agreement with the district, on terms agreed to by the parties, for:(1) the purchase or sale of water;(2) waste collection, transportation, processing, or disposal; or(3) any purpose relating to the district's powers or functions.(b) A contract or agreement under this section must comply with Chapter 791, Government Code.(c) A provision of district services or facilities to a member or an exercise of district power regarding a member's retail services may only be made through a contract between the district and the member under this section. Added by Acts 2009, 81st Leg., R.S., Ch. 523 (S.B. 1223), Sec. 1, eff. June 19, 2009.Amended by: Acts 2011, 82nd Leg., R.S., Ch. 586 (H.B. 3847), Sec. 7, eff. June 17, 2011.